The Important Reason You Need to Wash Your Face Tonight (and No, It's Not Because of Acne)

Between Valentine's Day, Fashion Week, and the Grammys, you might have missed some breaking skin care news last weekend: A new study suggests that air pollution (think anything from smog to cigarette smoke to car exhaust) may lead to liver spots (a.k.a. age spots) on your skin.

You're not alone if your first thought is, Whatever. Liver spots? Your great aunt Pam probably has them. But liver spots are actually pretty common among people under the age of 35 and especially among Caucasians (although people of all ethnicities can get them). "Liver spots are brown spots that can occur anywhere, but are particularly common on the face, chest, and arms," explains Joshua Zeichner, M.D., dermatologist and director of cosmetic and clinical research in dermatology at Mt. Sinai Hospital in NYC. "Unlike freckles, which fade in the winter, liver spots are permanent and are a direct result of damage to the skin." If you get one, it's with you for life.

But how does the gunk in the air even get into your skin? A quick science lesson: Air pollution is made up of tiny particles called particulate matter, or PM. The problem with them is in their size; they're so small that they're able to sink deep into skin's layers, where they wreak havoc on your cells and create a free-radical free-for-all (free radicals are the molecules that destroy collagen and elastin, damage DNA, and basically ruin your life). It doesn't end there. "The free-radical damage and inflammation in the skin caused by air pollution stimulate your pigment-producing cells, forcing them into overdrive," says Zeichner. This uptick in pigment leads to (of course) hyperpigmentation—in the form of those liver spots.

Cleansing is key because PM gets a chance to harm your skin cells and cause liver spots only if you let it hang out there. If you wash your skin thoroughly once you're in for the night, you drastically minimize the odds of long-term damage. But you can't just splash some soap on your face and call it a day, since PM is so small that that won't really do anything. Instead, wash using an oil cleanser like Shiseido Perfect Cleansing Oil ($32, bloomingdales.com). Oils actually dissolve PM along with makeup and other grime, says Zeichner, and they do so gently, so this is ideal if you have sensitive skin. Or you can go the extra mile with a facial cleansing brush. "Some sonic facial brushes actually remove particulate matter much better than hand washing," adds Zeichner. In fact, studies show that the Clarisonic Mia Brush ($99, sephora.com) in particular removes 30 times more pollution than your own two paws. Real overachievers can do both in the form of the double cleanse (naturally, another Korean beauty innovation).

Think of air pollution as the new UV. The two have a lot in common: They both create free radicals, lead to wrinkles, and impair your DNA (which has the potential to result in skin cancer). So beyond cleansing, you should tackle this like you would the sun and protect yourself. Pile on the antioxidants, which prevent PM from making itself comfortable on or in your skin. "Vitamins C and E—along with other likes ferulic acid and phloretin—are key players," says Zeichner. Look for blends like Skinceuticals C E Ferulic ($162, apothica.com) and DermaDoctor Kakadu C 20% Vitamin C Serum With Ferulic Acid and Vitamin E ($95, macys.com), since these antioxidants work synergistically to boost each other's efficacy. You can also upgrade your sunscreen from a no-frills type to one that offers built-in protection against environmental aggressors (read: pollution). Dior's One Essential City Defense Toxin Shield Pollution and UV Advanced Protection SPF 50 ($59, nordstrom.com) is super-powered by red hibiscus extract, which forms a seal over skin so PM can't get in—and even makes it tough for PM to stick to the skin's surface at all. Meanwhile, Shiseido Urban Environment Oil-Free UV Protector Broad Spectrum SPF 42 ($32, saks.com) pairs sunscreen with antioxidants like vitamin E for a double dose of protection for your skin.

It's not like you shouldn't go outdoors for the sake of perfect skin—and if you take the right steps, you don't have to worry too much. Just remember that not washing your face before bed could have more serious consequences than just raccoon eyes in the A.M.

Now it's time to master the cleanse. Watch how to wash your face like a pro: